add fork bash script

helpers/fork.sh

@@ -0,0 +1,46 @@
+#! /bin/bash
+
+source lib/utils/helpers/common.sh
+
+function main {
+    if [ ! -f .env ]; then
+        echo ".env not found!"
+        exit 1
+    fi
+    source .env
+
+    echo "Which chain would you like to fork ?"
+    echo "- 1: Ethereum Mainnet"
+    echo "- 2: Arbitrum"
+    echo "- 3: Polygon"
+    echo "- 4: Gnosis"
+    echo "- 5: Avalanche"
+    echo "- 6: Base"
+    echo "- 7: Binance Smart Chain"
+    echo "- 8: Celo"
+    echo "- 9: Polygon ZkEvm"
+    echo "- 10: Optimism"
+    echo "- 11: Linea"
+
+    read option
+
+    uri=$(chain_to_uri $option)
+    if [ -z "$uri" ]; then
+        echo "Unknown network"
+        exit 1
+    fi
+
+    echo "What block do you want to fork ? (Can leave empty for instant)"
+
+    read block
+
+    if [ -z "$block" ]; then
+        echo "Forking $uri"
+        anvil --fork-url $uri
+    else 
+        echo "Forking $uri at block $block"
+        anvil --fork-url $uri --fork-block-number $block
+    fi
+}
+
+main